cyclist lance armstrong loses all seven of his tour de france titles, is banned from the sport for life, and steps down from his livestrong foundation after an investigation finds he cheated throughout his career. daredevils rise to the challenge. nik wallenda becomes the first person to tightrope-walk directly over the niagara falls. and fearless felix baumgartner breaks the speed of sound skydiving from the edge of space. london and the royal family celebrate the summer olympics, queen elizabeth's diamond jubilee, and the announcement of an expected royal heir. and that's a look at some of the biggest headlines of 2012. for "teen kids news," i'm anna kooiman, "fox news channel in the classroom." >> here's another report in our series on first aid basics. >> attila the hun, jazz musician tommy dorsey, and the man who wrote the play "streetcar named desire," tennessee williams -- they all had one thing in common. they choked to death. >> choking is very common, and with the proper training, you can learn how to help someone who might be choking. >> what is choking? >> choking occurs whe